DIY: Unlocking iPhone 3G/3Gs with iOS 4.1 using redsn0w


[Update 01-Feb-2011: This procedure also works on an iPhone 3G on iOS 4.1. I have personally tried it. The only difference is that you have to download the iOS 4.1 firmware for the 3G instead of the 3Gs. And yes, they are different.] 

[If you are interested in unlocking a first generation iPhone, then refer this post.]

A sleepless night trying to unlock my new iPhone 3Gs got me into writing this tutorial. Although the unlocking procedure was rather simple, it took me a very long time to sift the grain from the chaff. There is a lot of conflicting, half cooked information out there. Plus I had a gazillion questions that I didn’t know whom to ask.

I have put together this DIY so that people in the same situation wont have to go through the same hell as me.

Without further ado lets get started.

But first…

let my answer some basic questions that you might have

What does this procedure apply to?

The procedure described here helps you jailbreak and unlock your iPhone 3Gs that is on iOS 4.1 with 5.14.XX baseband.

What if I am on a different firmware/baseband?

This tutorial may not apply to you. Sorry, buy you will have to Google it.

Why do I have to jailbreak? Cant I just unlock?

No. Jail breaking helps you run apps that are not approved by Apple (didn’t come from the Apple app store). The app that performs the unlock is one such app.

Will this work??!!!

Yes. I have personally tried it on my 3Gs (and also on a 3G).

Great. What do I need?


  • iTunes 10.1 (Download from the site)
  • iPhone firmware 4.1 (Download from here)
  • iPad firmware 3.2 (Download from here)#
  • redsn0w 0.9.6 (Download the mac version from here and the Windows version here)
  • Wireless Internet connection.

Ok before we begin, I need to tell you this. This unlock works by upgrading your firmware to the iPad’s 6.15 baseband. That’s right, the iPad’s baseband. There was a hole in the basebands that came with iPhone firmware 5.13.04 and earlier, that could have been exploited to perform a carrier unlock. But this flaw has been fixed by Apple in the later releases (damn!) but luckily for us the iPad 6.15.00 baseband that comes with the 3.2 firmware has the same flaw (yay!) This is the reason you need to upgrade the baseband if you need to perform the unlock.


What’s the catch?

Ok first of all, the baseband is an iPad baseband although it seems to work fine with the iPhone 3Gs . This is not a problem in itself but what you need to know is that once you update the baseband, there’s no going back! You cannot downgrade the baseband. Due to this you will be instantly voiding you warranty because if you take it to an Apple store for service they will know what you did. Plus, if Apple releases a 5.XX.XX baseband with any fixes, you wont be able to upgrade the baseband as you are already on a higher version! Downgrading of the baseband is not allowed.

Another drawback is that if you decide that you don’t need the jailbreak (or the unlock for that matter) you wont be able to restore the firmware back to 4.1 using iTunes. You are stuck with the jailbreak! (unless the dev team finds some way around it)

Ok this is very important: some people who performed the unlock have reported that the GPS feature has stopped working for them. So for the sake of argument lets assume that you will lose GPS with this unlock.

Before you proceed make sure you understand the above risks well. In fact, go ahead and read it again. I’ll wait.


Is there no other way to unlock?

Unfortunately no. This is the only way available at the time this article was written.

Now that you understand what you are getting into, lets get started.

Download the 4.1 firmware, 3.2 firmware and redsn0w and put them all in the same folder.

Launch redsn0w. Important: On Windows 7/Vista/Windows 2008 make sure you run redsn0w under the administrative account. (Right click redsn0w and select Run as administrator)

Click on browse and select the 4.1 firmware.

redSn0w will ask you to check if you have a newer model of the iPhone 3Gs. The steps to do this is explained in the popup. If it’s a newer model click yes, else click no.

redsn0w newer iPhone 3gs prompt

The program will now prepare the jailbreak data

In the next prompt, select Install Cydia and Install iPad baseband. When you select the iPad baseband option, it will warn you. Basically it’s the same thing I said before we started the tutorial. Click Yes to continue.

redsn0w iPad baseband warning

Now redsn0w is ready to start the actual jailbreak process. Plug in the iPhone and then turn it off. If you turn it off and then plug it in, it will turn right back on. So don’t do that.

redsn0w iPad baseband warning

The next step will require you to put the phone in DFU mode. That’s the mode the iPhone enters to enable a firmware restore. The next screen will explain the steps to do this. It is very critical to get it right to continue with the jailbreak process. So before you click next, familiarize yourself with the steps.

First you will need to press and hold the power button (the button on top of your phone) for around 3 seconds. Next, WITHOUT releasing the power button, press and hold the home button (the round button at the bottom of the screen) around 10 seconds. Finally, release the power button but DO NOT release the home button.

If you did the steps properly, redsn0w will automatically move to the next screen.

IMPORTANT: Ensure that your computer is connected to the Internet at this point. The version of redsn0w I used pulls data from the net, so a connection is important to complete the jailbreak.

Ready? Click next.

redsn0w DFU screen

Perform each of the steps as mentioned in the screen. The program will automatically move to the next screen and start downloading the jailbreak data to the phone. Once you reach that screen, release the home button.

#IMPORTANT: In the requirements section, I had asked you to download the iPad firmware too. This may nor may not be required because at the time of writing, redsn0w was designed to download the required data directly from Apple’s servers. If you wish, you can try to perform the jailbreak without downloading the firmware. I just played safe and downloaded it, all the same.

After the download is complete, you will move to the next screen which says that the rest of the jailbreak will happen on your phone. Click on the close button to close redsn0w.

Wait for the jailbreak to complete and for the phone to restart. Once you see the slide to unlock screen, you are done.


Here comes the unlock.


Connect the phone to a wireless access point.

Launch Cydia. Wait for Cydia to complete whatever is doing (this will take some time, so be patient).

Tap on Manage > Sources

Tap Edit and then Add

In the dialog that appears enter: (that’s a zero in there not the letter o) and tap Add Source.

Once it has been added, tap on the entry, select ultrasn0w and tap on install.

Cydia will install ultrasn0w and unlock the phone.

Restart the phone, put in your SIM and start it up again.

The phone might say No Service for some time but it should ultimately change to the name of your network provider.

Congratulations! You now have an unlocked iPhone.


Wait! You are not done yet


Some people have reported battery issues after unlocking their iPhones. This has something to do with the phone trying to retrieve valid activation keys from the net at regular intervals. A chap going by the handle of sbingner has devised a method to give each phone a legitimate activation ticket. His hack is called SAM (Subscriber Artificial Module).

The information on how to use this hack is bit hazy so I will tell you the method that worked for me.

Open up Cydia.

Tap on Manage > Sources

Tap Edit and then Add

In the dialog that opens enter, and tap on Add Source

Tap the entry you just added and install SAM

Once installation is complete, quit Cydia.

Go to Settings > SAM, tap on Revert lockdown to Stock

Next tap on De-Activate iPhone

Restart your phone, plug it in to your computer and launch iTunes.

You will briefly see a message on your phone which says Activating iPhone.

Go back to Settings > SAM.

Next to Activation State it should now say WildcardActivated.




That’s it. You are done. Enjoy your new unlocked iPhone.


If something didn’t work out, leave a comment and I will do my best to help you out. Also, if the unlock worked, do let me know if you are one of the lucky ones for whom GPS works.

Have fun